You can put this solution on YOUR website! what is 1 mile divided by the time 2hr 30 min and 26 seconds
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2hr 30min and 26sec = (2+(30/60)+(26/3600)) = 2.507222.. hrs
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Your Problem:
(1 mile)/(2.507222) = 0.39885 miles per hour
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Cheers,
Stan H.